在64位CPU上的C++中的Mac OS X上,是否有64位的类型？

Question

我不能用"长久"; 我该怎么用？

Answer 1

假设Snow Leopard(Mac OS X 10.6.2 - Intel),那么'long'是默认编译器的64位.

指定'g ++ -m64',它在早期版本中也可能是64位.

 1 = sizeof(char)
 1 = sizeof(unsigned char)
 2 = sizeof(short)
 2 = sizeof(unsigned short)
 4 = sizeof(int)
 4 = sizeof(unsigned int)
 8 = sizeof(long)
 8 = sizeof(unsigned long)
 4 = sizeof(float)
 8 = sizeof(double)
16 = sizeof(long double)
 8 = sizeof(size_t)
 8 = sizeof(ptrdiff_t)
 8 = sizeof(time_t)
 8 = sizeof(void *)
 8 = sizeof(char *)
 8 = sizeof(short *)
 8 = sizeof(int *)
 8 = sizeof(long *)
 8 = sizeof(float *)
 8 = sizeof(double *)
 8 = sizeof(int (*)(void))
 8 = sizeof(double (*)(void))
 8 = sizeof(char *(*)(void))

经测试:

i686-apple-darwin10-g++-4.2.1 (GCC) 4.2.1 (Apple Inc. build 5646) (dot 1)
Copyright (C) 2007 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

在带有选项的Mac OS X 10.7.5上使用GCC 4.7.1进行编译,-std=c99程序的输出更加广泛.感谢apalopohapa指出了long long原来缺少的疏忽.

 1 = sizeof(char)
 1 = sizeof(unsigned char)
 2 = sizeof(short)
 2 = sizeof(unsigned short)
 4 = sizeof(int)
 4 = sizeof(unsigned int)
 8 = sizeof(long)
 8 = sizeof(unsigned long)
 4 = sizeof(float)
 8 = sizeof(double)
16 = sizeof(long double)
 8 = sizeof(size_t)
 8 = sizeof(ptrdiff_t)
 8 = sizeof(time_t)
 8 = sizeof(long long)
 8 = sizeof(unsigned long long)
 8 = sizeof(uintmax_t)
 1 = sizeof(int8_t)
 2 = sizeof(int16_t)
 4 = sizeof(int32_t)
 8 = sizeof(int64_t)
 1 = sizeof(int_least8_t)
 2 = sizeof(int_least16_t)
 4 = sizeof(int_least32_t)
 8 = sizeof(int_least64_t)
 1 = sizeof(int_fast8_t)
 2 = sizeof(int_fast16_t)
 4 = sizeof(int_fast32_t)
 8 = sizeof(int_fast64_t)
 8 = sizeof(uintptr_t)
 8 = sizeof(void *)
 8 = sizeof(char *)
 8 = sizeof(short *)
 8 = sizeof(int *)
 8 = sizeof(long *)
 8 = sizeof(float *)
 8 = sizeof(double *)
 8 = sizeof(int (*)(void))
 8 = sizeof(double (*)(void))
 8 = sizeof(char *(*)(void))
 1 = sizeof(struct { char a; })
 2 = sizeof(struct { short a; })
 4 = sizeof(struct { int a; })
 8 = sizeof(struct { long a; })
 4 = sizeof(struct { float a; })
 8 = sizeof(struct { double a; })
16 = sizeof(struct { char a; double b; })
16 = sizeof(struct { short a; double b; })
16 = sizeof(struct { long a; double b; })
 4 = sizeof(struct { char a; char b; short c; })
16 = sizeof(struct { char a; char b; long c; })
 4 = sizeof(struct { short a; short b; })
 6 = sizeof(struct { char a[3]; char b[3]; })
 8 = sizeof(struct { char a[3]; char b[3]; short c; })
16 = sizeof(struct { long double a; })
32 = sizeof(struct { char a; long double b; })
16 = sizeof(struct { char a; long long b; })
16 = sizeof(struct { char a; uintmax_t b; })

Answer 2

包括<stdint.h>or <inttypes.h>（后者在更多编译器上找到，但两者都由 Apple 编译器提供），并使用uint64_tand int64_t。它们在 32 位和 64 位目标上都是 64 位的。